It is well known to provide a vertically movable patient support. More particularly, it is known to provide a hospital bed including a base frame and an elevating frame supporting a patient support surface. A lifting mechanism is configured to raise and lower the elevating frame relative to the base frame. Entry and exit from the bed is facilitated by placing the elevating frame in a lowered position. A raised position of the elevating frame, in turn, provides a convenient surface for the examination and treatment of the patient.
Additionally, conventional lifting mechanisms provide for the tilting of the elevating frame from a horizontal position into Trendelenburg and reverse Trendelenburg positions. A hospital bed incorporating such a lifting mechanism is illustrated in U.S. Pat. No. 3,958,283 to Adams et al., the disclosure of which is expressly incorporated by reference herein.